Hello !
I separated 'moodledata' folder (on computer 2) from rest of MOODLE (on computer 1) using NFS in Ubuntu. How to measure communication time between these modules?
Will 'ping' command be OK? But, if we have more than one module on computer, how then do it?
To measure time of execution of modules I use NuSphere software (but it works properly under Windows, so I must restore copy of Moodle from Ubuntu in Windows), but I don't have an idea how to measure communication time between modules.
Best regards,
Artur
In reply to Artur Zacniewski
Re: Communication time between modules and time of execution
by Visvanath Ratnaweera -
I don't understand the problem. As I see it, your computer 1 is the webserver and $CFG->dirroot, where the Moodle scripts are, is in a harddisk physically attached to it. The $CFG->dataroot, where the uploaded files go, is in computer 2 and mounted via NFS to computer 1.
You want to know how much "slower" the NFS mounted file system is as compared to a harddisk physically attached to computer 1?
Now "slower" in doing what? If you want to know the effect on the running Moodle system, what is the purpose of testing on a different (Windows) machine? If you mean the performance of this NFS filesystem itself, there are different tools for that. But that has nothing to do with Moodle.
It would be easier for us if you describe your aims and reasons for the whole experiment.
You want to know how much "slower" the NFS mounted file system is as compared to a harddisk physically attached to computer 1?
Now "slower" in doing what? If you want to know the effect on the running Moodle system, what is the purpose of testing on a different (Windows) machine? If you mean the performance of this NFS filesystem itself, there are different tools for that. But that has nothing to do with Moodle.
It would be easier for us if you describe your aims and reasons for the whole experiment.
In reply to Visvanath Ratnaweera
Re: Communication time between modules and time of execution
by Dale Davies -
I think the question is more like...
Does having the dataroot stored on a seperate machine introduce some latency over one stored on the local machine?
Or...
How do I measure the time it takes (using Linux) to access a file stored locally, compared to accessing a file stored on a seperate machine?
Unfortunately I cannot provide much of an accurate answer to either of these, apart from to say I suppose accessing a file on a network share would probably be a bit slower, but I'm not sure you would notice it if the network throughput was good enough and you have files stored on a nice fast machine with a fast hard drive.
Does having the dataroot stored on a seperate machine introduce some latency over one stored on the local machine?
Or...
How do I measure the time it takes (using Linux) to access a file stored locally, compared to accessing a file stored on a seperate machine?
Unfortunately I cannot provide much of an accurate answer to either of these, apart from to say I suppose accessing a file on a network share would probably be a bit slower, but I'm not sure you would notice it if the network throughput was good enough and you have files stored on a nice fast machine with a fast hard drive.
In reply to Dale Davies
Odp: Re: Communication time between modules and time of execution
by Artur Zacniewski -
Both of these two question are right. I assumed, that files on the second machine are "stored on a nice fast machine with a fast hard drive"
In reply to Artur Zacniewski
Re: Odp: Re: Communication time between modules and time of execution
by Dale Davies -
There is probably some formula to work it out, but unfortunately I'm not clever enough to work it out. I have wondered the same myself as we considered moving the moodledata folder onto another server with greater storage capacity.